Using the expression 7x = 3y is 35, what is x?

7x = 3y

y = 35

plug in 35 for y

7x = 3(35)

simplify, multiply 3 and 35 together

3(35) = 105

7x = 105

isolate the x, divide 7 from both sides

7x/7 = 105/7 

x = 15

15, A is your answer

For #2:

Bruce has 97 sports card. 34 are football cards. Find y, which are the amount of sports cards not foot ball cards

34 + y = 97

34 (-34) + y = 97 (-34)

y = 97 - 34

y = 63

hope this helps